The 'Tachylemme' ready reckoner, c 1876.
- Made:
- circa 1876 in Paris
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"Tachylemme" of C. L. Chambon, c. 1876.
The Tachylemme provides a simple means of calculating the daily interests on sums of money, based upon a ‘year’ of 360 days.
Units, tens, hundreds and thousands are each represented on a separate paper table on the surface of a cylinder. By rotating the knobs on the left of the instrument, the sum of money is set in the extreme left column. The daily interest on that sum is read off by addition of the column beneath the correct annual interest rate.
The total capacity is 9999, and the Tachylemme can be used for any currency unit, as the interest sums are given in decimals.
Details
- Category:
- Mathematics
- Object Number:
- 1936-195
- Materials:
- glass, metal (unknown), wood (unidentified) and paper (fibre product)
- Measurements:
-
overall: 40 mm x 165 mm x 100 mm, 0.45 kg
- type:
- ready reckoner
- credit:
- Mr L. Malassis
